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Information × Registration Number 0220U104204, 0120U104992 , R & D reports Title Development of selection criteria for single-sector HPHT-diamond plates synthesized using new compositions of carbon solvents, for their use in Schottky diodes and heat sink substrates, substantiation of their design and physical principles of operation. popup.stage_title Head Strelchuk Viktor V., Доктор фізико-математичних наук Registration Date 14-12-2020 Organization VE Lashkarev Institute of Semiconductor Physics of the National Academy of Sciences of Ukraine popup.description2  The concept of semiconductor vertical Schottky diodes, substrates for CVD epitaxy, and a heat sink based on single-sector HPHT-diamond plates was developed. The performance of Schottky diodes was optimized by selecting the parameters of the diode drift layer taking into account the projected reverse breakdown voltage. The most promising substrates for CVD epitaxy of Schottky diodes is a single sector {100} HPHT diamond plate. For vertical diodes, conductive type IIb diamond substrates are required, and for pseudo-vertical diodes - insulating substrates of type Ib and IIa with the minimum possible number of structural defects and impurities. The concentration of surface dislocations and uncontrolled impurities should be controlled with the density of etching pits and by the photoluminescence method. The structure of a Schottky diode is fabricated by MPCVD epitaxy of diamond layers on a single-sector HPHT diamond. To prevent threading defects, preliminary preparation of the HPHT-substrate is carried out using mechanical polishing and chemical etching in oxygen-hydrogen plasma. Before the formation of ohmic contacts, the diamond must be passivated with hydrogen, and the contacts are formed using Ti/Pt/Au deposition followed by annealing in a nitrogen atmosphere at T = 420 ÷ 500 °C. Before deposition of Schottky contacts, the diamond must be passivated with oxygen, and the contacts are formed by deposition Pt/Au followed by thermal annealing at T = 400 °C. A method to optimize the thermal insulation properties of the cell’s materials using FTIR spectroscopy was developed. For composites based on cesium chloride, the IR transparency decreases from ~ 70% to less than 0.1% with an increase in zirconium dioxide content up to 50% by weight, which is due to an increase in the number of optical boundaries. For composites with graphite, a change in the graphite content from 0.02 to 0.38 wt% increases the IR blocking ability of the insulation layer from ~ 0.7 to 0.999. Product Description popup.authors Danylenko Ihor M. Malyuta Serhii V Nikolenko Andrii S. Stubrov Yurii Yu. popup.nrat_date 2020-12-14 Close